Flexible printed circuit boards (“flexible strips”) populated with light-emitting diodes and totally encapsulated in potting compound by insert molding for IP protection purposes are well-known. Emission efficiency is lost in these devices, however, because of significant light losses in the potting compound. In order to avoid degrading the emission efficiency, an alternative option is known in which the potting compound does not extend over the top edge of the LED(s), and therefore the LED(s) together with the typical uppermost light-emitting surface thereof is (are) no longer covered by the potting compound. With this alternative there is on the other hand a risk that when bending occurs cracks will form between the potting compound and the housing side of the LED, which can result in breaks in the seal and ingress of moisture, dust, etc. into the flexible strip.